Nematocidal composition and method containing dialkyl and dialkenyl n,n&#39;-bis(substituted carbamoyloxy) dithioloxalimidates



United States Patent O 3,514,516 NEMATOCIDAL COMPOSITION AND METHODCONTAINING DIALKYL AND DIALKENYL N,N'-BIS(SUBSTITUTED CARBAMOYLOXY)DI-THIOLOXALIMIDATES John C. Summers, Wilmington, DeL, assignor to E. I. duPont de Nemours and Company, Wilmington, Del., a corporation of DelawareNo Drawing. Filed Aug. 18, 1967, Ser. No. 661,510 Int. Cl. A01n 9/20 US.Cl. 424-327 9 Claims ABSTRACT OF THE DISCLOSURE Chemical compounds ofthe class dialkyl and dialkenyl N,N'-bis(substitutedcarbamoyloxy)dithioloxalimidates, such as dimethylN,N-bis(methylcarbamoyloxy)dithioloxalimidate, useful in preventing thedestructive effects of nematodes.

BACKGROUND AND SUMMARY This invention relates to chemical compoundsuseful as nematocides and is more particularly directed to dialkyl anddialkenyl N,N'-bis(substituted car bamoyloxy)dithioloxalimidates of thefollowing formula, and their use as nematocides:

R and R can be the same or different and are alkyl of one through 4carbon atoms or alkenyl of three through four carbon atoms; and

R and R can be the same or different and are hydrogen, alkyl of onethrough four carbon atoms, alkenyl of three through four carbon atoms orpropargyl.

Compounds of Formula I wherein R is the same as R and R is the same asR; are preferred because of their economy of manufacture.

While there is an ever growing number of chemical nematocides availableto the public there is also a continuing need for nematocides whichpossess desirable physical properties, desirable nematocidal activity,or desirable nematocidal activity and good tolerance by plants andanimals.

In the context of this disclosure the term nematocide is employed todesignate a compound that kills, inactivates, repels or otherwiseprevents the destructive effects of plant parasitic nematodes, at anystage in the life cycle of said nematodes.

In most areas of the world, the solids used for agricultural orhorticultural pursuits contain populations of plant parasitic nematodes.Losses due to nematodal infestation range from moderate reductions inyield to complete elimination of the harvest. Therefore, effective andeconomical methods of preventing crop reduction due to this widespreadpest are needed.

The term nematode, unless otherwise indicated, is intended to refer toand include all life forms, such as eggs, larvae and adults ofplant-parasitic members of the phylum Nemata. These are generallyunsegmented worms under one-eighth of an inch in length. Most speciespresent in the soil attack the roots or other underground parts ofplants. Some species, however, attack the above ground plant parts suchas the crown, stem, leaves, buds or seeds.

The parasitic nematodes damage crops and reduce useful produce in anumber of ways. Species which attack plants largely from the outside arecalled ectoparasites.

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Their feeding often results in the death of the rootlets involved. Whenthe numbers of such nematodes are large, many rootlets are killed,resulting in reduced growth and limited yields of the infested crop.

Species which enter and live within root tissue are calledendoparasites.

Both ectoparasitic and endoparasitic nematodes can cause a malformationof the affected plant part and can even cause the death of the tissuesurrounding the point of attack. Such effects not only reduce thegeneral vigor of the plant, but, in many cases, actually destroy themarket value of the crop. One example of this loss of marketabilityoccurs when carrots affected in this fashion are malformed therebylosing their marketability.

Furthermore, damage caused by plant-parasitic nematodes can serve asentry courts for other plant pathogens such as fungi, bacteria andviruses. Therefore, it is also intended that the compounds of thisinvention be used in combination with other pesticides, such asfungicides, bacteriocides and virucides.

The most efficient operation of a farm unit often requires thatsusceptible crops be planted in an area known to contain damagingpopulations of plant-parasitic nematodes. In the case of establishedperennial crops, plantparasitic nematodes may invade establishedperennial crops such as tree fruit, sugarcane and pineapple.

When nematodal infestation occurs the farm manager can increasefertilizer and water to offset damage to the root system or applychemicals to control the nematodes. At best, the additional fertilizerand water have proven to be expensive and only partially effective andwhen the nematode species is one that causes malformation of the producethis procedure is often of no value. Thus, the greatest hope forefiective nematode control lies in the use of chemical nematocides.

Many of the chemicals now available for the control of nematodes arephytotoxic and can be safely used only well in advance of the plantingof a crop. This need for a time lag between nematocidal application andplanting complicates the scheduling of cultural activities and, if'weather conditions restrict the planting period, may even prevent theapplication of the nematocidal chemical.

The compounds of this invention, however, do not damage plants whenapplied as herein described and, therefore, can he used before, duringor even after planting. In many instances, treatment with the compoundsof this invention is most efficient if delayed until after the youngcrop plants have become established.

In addition to phytotoxicity, previously available compounds orcompositions and methods for controlling nematodes often are high incost per unit of area treated; disagreeable to the operator by reason ofbeing malodorous, irritating, or lachrymatory; or have restrictedutility. The compounds and methods of this invention, however, are safeto seeds and growing plants at well above the necessary use rates; areeasily and safely handled; are able to provide an extended period ofprotection; and are economical to use due to theireffectiveness at lowrates. Therefore, the compounds and methods of this invention allow forpractical crop protection on a broad scale.

DESCRIPTION OF THE INVENTION As will be recognized by those skilled inthe art, the compounds of Formula I can exist in any or all of threeisomeric forms, with the relation of one carbamoyloxythiolimidategrouping to the other being syn-syn, synanti or anti-anti.

Those compounds of Formula I where R is the same as R and R is the sameas R are preferred because they are the most economical to manufacture.Of these compounds, dimethylN,N-bis(methylcarbamoyloxy)dithioloxalimidate and dimethylN,N'-bis(ethylcarbamoyloxy)dithioloxalimidate are most preferred becauseof their outstanding nematocidal activity and safety margin on crops.

Preparation The compounds of Formula I wherein R and R are the same andR and R are the same are prepared by reacting an appropriate mercaptanwith dichloroglyoxime in an inert solvent such as an alcohol-watermixture, followed by the addition of sodium hydroxide to give thedesired dialkylmercaptoglyoxime. This reaction is illustrated byEquation A:

The dialkylmercaptoglyoxime obtained in reaction A is then dissolved orsuspended in an inert solvent or diluent such as methylene chloride,cyclohexane, chloroform, carbon tetrachloride, benzene, toluene, xyleneand the like. An appropriate isocyanate is then added to this solutionor suspension to obtain the desired compound of Formula I. This reactionis illustrated by Equation B:

To prepare those compounds of Formula I wherein R and R are different,reaction A is performed stepwise with the addition of one equivalent ofR SH and sufficient sodium hydroxide to neutralize the mixture followedby the addition of one equivalent of RzSH and a second portion of sodiumhydroxide.

To prepare those compounds of Formula I wherein R and R are different,reaction B is performed stepwise with the addition of one equivalent ofR NCO to the appropriate dialkylmercaptoglyoxime followed by theaddition of one equivalent of R NCO.

The dichloroglyoxime starting material for Equation A is prepared by thechlorination of glyoxime, as illustrated in Equation C:

HON

NOH

The preparation of dichloroglyoxime by the chlorination of glyoxime isdescribed by Brintzinger and Titzmann Ber. 85, 344(1952).

Nematodes controlled Representative of the nematodes from which thecompounds of Formula I offer protection are the following:

Corn nematodePratylenchus zeae Dagger nematodeXiphinema diversicaudalumGolden nematode-Heter0dera rostochiensis Grass nematode-Anguina agrostisKidney-shaped nematode-Rotylenchus reniformis Lance nematodes-Hpl0Iaim-us spp.

Meadow nematodes-PratyIenchus spp.

Northern root-knot nematodeMel0id0gyne hapla Pea rootnematode-Heter0dera gottingiana Peanut root-knot nematodeMel0id0gynearenaria Potato rot nematodeDitylenchus destiructor RicenematodeDitylenchws angustus Ring nematodesCric0nem0ides spp.

Smooth-headed lesion nematodeP/'atylcnclzus brachyurus Southernroot-knot nematode-Mel0idogyne incognita Soybean cyst nematodeHeteroderaglycines Spiral nematodes-Helicotylenchus spp.

Stern and bulb nematodeDitylenchus dipsaci Sting nematodesBel0nolaimusspp.

Stubby-root nematodesTrichodorus spp.

Sugar beet nematode-Heterodera schachtii Tobacco cyst nematodeHeter0deratabacum Tobacco stunt nematodeTylenchorlzynchus claytoni Wheatnematode-Anguina tritici Formulations Compositions of this inventionsuitable for practical use as nematocides will include one or morecompounds of Formula I above either individually, in admixture with eachother, or in admixture with other pesticides, and can includesurface-active agents, solid or liquid diluents and other materials asdescribed to produce wettable powders, suspensions, emlulsifiableconcentrates, dusts, solutions, granules, pellets or high-strengthcompositions.

Wettable p0wders.-The nematocidal compounds of this invention arefrequently applied on or in the soil. This can be done by dispersingthem in water and spraying this mixture on the soil with or withoutsimultaneous or subsequent tillage to incorporate them into the soil.Similarly the compounds of this invention can be dispersed in volatileoils and applied in the same manner. The compounds of this invention canbe conveniently formulated as a wettable powder to efficientlyaccomplish this result as the solubility of the compounds of thisinvention in both water and organic solvents is low, but finite. Tankmixtures of wettable powders with oils or water at concentrationssuitable for normal use will have all or part of the active material insolution rather than in suspension.

Formulations in the form of wettable powders are physically stable, freeflowing compositions comprised of effective amounts of compounds of thisinvention, surfactants and inert extenders.

The surfactants useful in formulating the compounds of this inventionact as wetting, dispersing and emulsifying agents and result in a rapidwetting and dispersion of the powder formulations in either water ororganic media. The surfactants can include such anionic, non-ionic andcationic agents as have been used heretofore in pesticidal compositionsof similar type. A detailed list of such agents is found in Detergentsand Emulsifiers 1966 Annual (John W. McCutcheon, Inc.).

Anionic and non-ionic surfactants are preferred in formulating compoundsof this invention. Of these the solid surfactants are most preferredbecause of ease of incorporation and elimination of caking problems thatmight otherwise occur. However, best dispersion of powders in an organicmedium is frequently obtained by use of a liquid non-ionic agent, whichnormally functions in an oil solution concentrate as an emulsifier.

Of those surfactants that act as wetting agents, the most preferred arealkyl benzene and alkyl naphthalene sulfonates; petroleum sulfonates;sulfated fatty alcohols; amines or acid amides; sulfonated or sulfatedfatty acid esters; sulfonated vegetable oils; long-chain esters ofsodium isethionate; and esters of sodium sulfosuccinate.

The most preferred non-ionic surfactants for dispersion in organic mediaare the polyethylene oxide adducts of alkyl phenols, fatty alcohols,sorbitol, sorbitan fatty acid esters and propylene oxide. Additionally,these non-ionic surfactants serve as wetting agents if the compositionis used in water instead of an organic media.

Surfactants most preferred for formulating wettable powders fordispersion in water are the sodium, calcium or magnesium salts of ligninsulfonic acids; sodium salts of polymeric alkyl naphthalene sulfonicacid; sodium salts of benzene sulfonic acid; alkyl substitutedpolyvinylpyrrolidine; sodium N-methyl-N-(long chain acid) taurates; lowviscosity methylcellulose; and low viscosity polyvinyl alcohol.

Inert extenders can also act as grinding aids, anticaking agents andpromoters of free flowing characteristics, in addition to providing bulkto wettable powders. Some extenders suitable for use in preparing thewettable powder formulations of this invention are clays, diatomaceoussilica and synthetic mineral fillers such as wood flour, shell flours orcorn cob flour. Preferred extenders are kaolinites, attapulgite clay,synthetic silicas and synthetic calcium or magnesium silicate.

The wettable powder formulations of this invention will contain fromabout 25 to 90 weight percent active material, from 0.5 to 3 weightpercent wetting agent, from 0.25 to 5 Weight percent dispersant and from2 to 74.25 weight percent extender.

Dusts.Formulations in the form of dusts are most readily prepared bydiluting an available wettable powder with an inert carrier in blendingequipment that will yield a homogeneous product with a concentration ofactive material of from 1 to 60 weight percent.

Suitable diluents for this purpose are clays, talc, pyrophyllite, groundphosphate rock, sericite or tobacco stern dust. The choice of diluent isusually based upon the cost and availability of the diluent in the areawhere formulation is carried out, as shipment of diluent or theformulated dust for any distance is usually uneconomic. Most suitablediluents are dense, rapid settling and free flowing. Since talc,sericite, phosphate rock, pyrophyllite and tobacco stern dust possessall of these described characteristics they are preferred over kaolinclay, when such materials are available to the local custom blender.

When economically feasible, the dusts are prepared at the point ofmanufacture of the nematocide by first micropulverizing the nematocidewith a minimum amount of a suitable dust diluent. This concentrate isthen blended with the remainder of the diluent. In this way all of thediluent can be kept dense and free from drifting tendency and only asmall amount is subjected to finer grinding.

Normally, however, the manufacturer prepares only a high strength dustbase using a small amount of dense, free flowing diluent, such asmicaceous talc for further dilution at the point of final formulation.Dispersants are omitted but a wetting agent can be added to aid wettingof the dust by moist soil.

Granules.-For-mulations in the form of granules are physically stable,particulate compositions containing a compound of Formula I whichadheres to or is distributed through a basic matrix of a coherent, inertcarrier of microscopic particle size. In order to aid leaching of theactive ingredient from the granule, a surfactant can be present.

Nematocides that are not gaseous or highly volatile liquids are oftenmost readily applied in the form of granules. Granular formulations ofthe compounds of Formula I can be made by application of the activematerial to preformed granules or by the granulation of mixtures ofpowdered active material and suitable inert extenders and binders.

Suitable preformed granules to which the active material canbe appliedinclude granular attapulgite; granular expanded vermiculite; granularpyrophyllite; granular pecan, walnut or other nut shells; and granularcorn cob.

Preferred preformed granules are those with a porous, absorbtivestructure. These include attapulgite, expanded vermiculite and granulesof the organic materials named above. All are suitable for applicationof active material from a solvent solution. Granular attapulgite ispreferred because of its ability to disintegrate when wet. When theactive material is to be applied as a powder with a sticking agent,granular expanded vermiculite is preferred.

Granular formulations prepared from preformed granules will contain fromabout 2 weight percent to.

about 10 weight percent of active material. They can also contain fromabout 0.25 weight percent to 10 weight percent wetting agent and from 2to 10 Weight percent of liquid, low volatile sticking agent. Thissticking agent is included in the formulation to prevent the segregationof powdered active material from the granular carrier and it can be anyliquid having low volatility and low phytotoxicity. Some suitablesticking agents include heavy mineral oil, glycols such as ethylene orpropylene glycol, dimethylphthalate, and long chain alcohols such aslauryl alcohol. A separate sticking agent may not be necessary when thewetting agent is a liquid, non-volatile surfactant such as an octyl ornonylphenol polyethylene oxide condensate. Rapidity of release desiredwill dictate the nature of the sticking agent used. When quick releaseand rapid solution of the active material by soil moisture is desired,the sticking agent should be a glycol or liquid, Water misciblesurfactant. Conversely, release of active material can be delayed byusing a hydrophobic sticking agent.

The application of active material to preformed granules is oftenaccomplished by dissolving the active material in an inexpensivevolatile organic solvent and applying this solution to the granules. Asmany of the compounds of this invention are only slightly soluble in theinexpensive volatile solvents normally used, only a limited amount ofmaterial can be incorporated within the pore structure of the granule.Therefore, an attempt to incorporate high levels of active materialleaves the active material on the outside surface of the granule wheretumbling or any excessive handling will result in fines that areexcessively high in active content and bulk coarse granules low inactive content.

Granules formed from powdered mixtures of active material and diluentshaving the active material distributed uniformly throughout the granuleare preferred if the concentration of active material is to be above 10percent. Furthermore, such granules can also be tailored for precisecontrol of the rate of disintegration and release of the active materialand may be the preferred form even with low strength granules.

There are a number of ways in which these homogeneous granules can beprepared. Dry compaction plus dry granulation and screening can be used.Alternatively, the mixtures can be moistened with water or othersolvent, then extruded and cut or moist granulated, dried and screened.Granules can also be made by controlled tumbling of powder plus binderas taught in US. Pat. No. 3,192,290.

The active content of these granules will range from about 2 weightpercent to 50 weight percent. However, granules containing from 5 weightpercent to 10 weight percent are preferred for optimum distribution. Theinert carrier can be kaolinite, bentonites of sodium andcalcium-magnesium types, attapulgite, gypsum, plaster of paris or anycombination of such mineral fillers.

The diluents themselves can be binders when moistened and dried, e.g.swelling bentonites and plaster of paris. Alternatively, minor amountsof other binders can be added such as methyl cellulose, gum arabic,polyvinyl alcohol, swollen starch or soluble lignin sulfonates. Thechoice of kind and amount of binding agent can be 7 used to control therate of disintegration of the granules in moist soil. Additional controlis also afforded by the addition of minor amounts of water solubleinorganic salts, such as sodium sulfate or ammonium sulfate. Waterpenetration of granules can be aided by the addition of small amounts ofWetting agents. Preferred granules can be prepared by dry granulatingthe pellets described in U.S. Pat. No. 2,992,090 substituting thecompounds of this invention as the active material in place of theherbicides of the patent, and then screening to give 30 to 60 meshgranules. Granular formulations can also be prepared according to themethods taught in US. Pat. No. 3,056,723 and US. Pat. No. 3,168,437 bysubstituting the compounds of this invention for the pesticides disclosed in these patents and then formulating according to the teachingsof these patents.

Compositions of this invention can be used to soil treatment, sprays ordips either alone or in admixture with insecticides, mitcides,fungicides or other nematocides. The following list is illustrative ofthe other pesticides that may be used in combination with the compoundsof this invention:

1,2,3,4,l0,l hexachloro 1,4,4a,5,8,8ahexahydrol,4-endoexo-5,S-dimethanonaphthalene;

1,2,3,4,5,6-hexachlorocyclohexane;

2,3,4,5,6,7,8,8 octachloro 4,7 methano 3a,4,7,7a-

' tetrahydroindane;

1, l l-trichloro-2,2-bis (p-chlorophenyl) ethane;

l,2,3,4,10,l0 hexachloro 6,7 epoxy 1,4,4a,5,6,7,8,8a-

octahydro-1,4-endoexo-5,8-dirnethanonaphthalene;

1,2,3,4,10,10 hexachloro 6,7 epoxy l,4,4a,5,6,7,8,8a-

octahydro-l,4-endoendo-5,6-dimethanonaphthalene;

1(or 3a),4,5,6,7,8,8 heptachloro 3a,4,7,7a tetrahydro-4,7-methanoindene;

1, 1 l -trichloro-2,2-bis (p-methoxyphenyl ethane;

1,1 dichloro 2,2 bis(p chlorophenyl)ethane; chlorinated camphene havinga chlorine content of 67-69%;

2-nitro-l 1 -bis (p-chlorophenyl butane;

1-naphthyl-N-methylcarbamate;

methylcarbamic acid, ester with phenol, 4-(dimethylamine)-3,5-dimethyl;

methylcarbamic acid, ester with 1,3-dithiolan-2-one oxime;

0,0diethyl-O-[2-isopropyl-4-methylpyrimid-6-yl] thiophosphate;

0,0-dimethyl-1-hydroxy2,2,2-trichloroethyl phosphonate;

0,0-dimethyl-S-( 1,2-dicarbethoxyethyl) dithiophosphate;

0,0-dimethyl-O-p-nitrophenyl thiophosphate;

0,0-diethyl-0-p-nitrophenyl thiophosphate;

0,0-di methyl-O- 3-chloro-4-nitrophenyl) thiophosphate;

di-2-cyclopentenyl-4-hydroxy-3-methyl-2-cyclopentenl-one chrysanthemate;

0,0-dimethyl-O-(2,2-dichlorovinyl) phosphate;

mixture containing 53.3% Bulan, 26.7% Prolan and 20.0% relatedcompounds;

0,0-dimethyl-O-(2,4,5-trichlorophenyl) phosphorothioate;

0,0-dimethyl-S-(4-oxo-benzotriazine-3-methyl) phosphoro-dithioate;

bis-(dimethylamino) phosphonous anhydride;

0,0-diethy1-O-(2-keto-4-methyl-7-a-pyranyl) thiophosphate;

0,0-diethyl (S-ethyl mercaptomethyl) dithiophosphate;

calcium arsenate;

sodium aluminofluoride;

dibasic lead arsenate;

2'-chloroethyl-l-me thyl-2-(p-tert-butylphenoxy)ethyl sulfite;

azobenzene;

ethyl 2-hydroxy-2,2-bis(4-chlorophenyl)acetate;-

0,0-diethyl-O- (2- (ethylmercapto) ethyl) thiophosphate2,4-dinitro-6-sec-butyl phenol;

O-ethyl O-p-nitrophenylbenzenethiophosphonate;

4-ch10rophenyl-4-chlorobenzene sulfonate;

p-chlorophenyl-phenyl sulfone;

tetraethyl pyrophosphate;

8 1,l-bis-(p-chlorophenyl)ethanol; 1,1-bis-(chlorophenyl)2,2,2-trichloroethanol; p-chlorophenyl-p-chlorobenzyl sulfide;bis-(p-chlorophenoxy) methane;

3-( l-methyl-Z-pyrolidyl) pyridine;

mixed esters of pyrethrolone and cinerolone keto-alcohols and twochysanthemum acids;

cube and derris, both whole root and powdered;

ryanodine;

mixture of alkaloids known as veratrine;

d1-2-allyl-4-hydroxy-3-methyl-2-cyclopenten-l-one esterified with amixture of cis and trans dl-chrysanthemum monocarboxylic acids;

butoxypolypropylene glycol;

p-dichlorobenzene;

2-butoxy-2-thiocyanodiethyl ether;

naphthalene;

1, l-dichloro-2,2-bis (p-ethylpenyl) ethane;

p-dimethylaminobenzenediazo sodium sulfonate;

quinone oxyaminobenzooxohydrazone;

tetraalkyl thiuram sulfides such as tetramethyl thiuram monosulfide ordisulfide and tetraethyl thiuram monosulfide or disulfide;

metal salts of ethylene bisdithiocarbamic acid, eg

manganese, zinc, iron and sodium salts;

pentachloronitrobenzene;

dodecylguanidine acetate;

N-trichloromethylthiotetrahydrophthalimide (captan);

phenylmercury acetate;

2,4-dichloro-6- (ochloroaniline -s-triazine;

N-methylmercury p-toluenesulfonanilide;

chlorophenolmercury hydroxides;

nitrophenolmercury hydroxides;

ethylmercury acetate;

ethylmercury 2,3-dihydroxypropyl mercaptide;

methylmercury acetate;

methylmercury 2,3-dihydroxypropyl mercaptide;

3,3-ethylenebis(tetrahydro-4,6-dimethyl-2H-l,3,5-

thiadiazine-Z-thione) methylmercury dicyandiamide;

N-ethylmercury-p-toluenesulfonanilide;

l,4-dichloro-2,5-dimethoxy benzene;

metal (e.g. iron, sodium and zinc), ammonium and amine salts of dialkyldithiocarbamic acids;

tetrachloronitroanisole;

hexachlorobenzene;

hexachlorophene;

methylmercury nitrile;

tetrachloroquinone;

N-trichloromethylthiophthalimide;

1,2-dibromo-3-chloropene;

1,2-dibromo-3-chloropropene;

dichloropropane-dichloropropene mixture;

ethylene dibromide;

chloropicrin;

sodium dimethyl dithiocarbamate;

l,4-dichloro-2,S-dimethoxybenzene; and

2-(carboxyarnino)-l-benzimidazolecarboxylic acid,

dimethyl ester.

The use of pesticides such as those listed above in combination with thecompounds of this invention and employed according to the methods ofthis invention appears, in many instances, to enhance the plantprotectant power of the compositions of this invention. This increase inthe degree of plant protection is most often encountered when thepesticide used in combination with a compound of this invention is afungicide. This is especially noted when both plant-parasitic nematodesand fungi are present at the locus of treatment.

Application.'In applying the compounds of Formula I for nematodecontrol, the compound is of course applied in an amount sufficient toexert the desired action. The required amount, however, will be governedby such variables as method of applications, area of application, timeof year, temperature, moisture and the like.

The compositions of this invention can be used to control soilinhabiting plant-parasitic nematodes by incorporation in the soil priorto or during the planting of the crop to be protected. Treatment caninvolve the complete field (broadcast), a strip of pre-determined widthcen- The following illustrative examples are provided in addition tothose above to more fully describe this invention. Parts and percentagesare 'by weight unless otherwise noted.

EXAMPLE 1 tered on i crop row a at each indiviiual To a solution of 60parts dichloroglyoxime dissolved in fiz g g g gsfig g gf 33 3:32 1?z fgg zg 800 parts ethyl alcohol and 800 parts water is added, at 0-10" 0.,98 parts methyl mercaptan. Then 218 parts can be apphed alone combmatlonwith i 50% sodium hydroxide is added to make the system SO11 trea'fmentsas fertlilzers' Use rates for 6 6 slightly basic. Recrystallization ofthe resulting precipilifib g a ii i g bf ifig zst iv e i r i te ria l per 11132 3; gs f tatate from 2B-alcohol gives 100 partsdimethylmercaptoactually treated. More preferred rates for this type ofrFg g fig g ggg gfggxgfi gi in appliqation are in the rapge of 1 to 50of active 200 parts methylene chloride is added parts methyl maienal Per.hectare wlth rate i 2 to 25 kilograms of 15 isocyanate in 50 partsmethylene chloride. Filtration after active material per hectare belngmost preferred for 2 hours gives 23 parts dimethyl ,N,N, bis(methylcarreasons of economy' bamol ox d'tholo l' 'd t M 89-l97 C Two Thecompositions of this invention can .also be f recryszallii tti on s fr lb e r iitrile givs material melting tively used to control nematodes inthe soil by applylng at 194495 50 C them to the surface of the soil andpermitting them to be EXAMPLES carried by rainfall or irrigation waterto the root zone of 9 the plants to be protected. The solubility of thecom- The following indicated products can be prepared pounds of thisinvention is such that they move downby the procedure of Example 1 bysubstituting an equiward slowly with percolating water. The compounds ofvalent weight of the indicated mercaptan for the methylthis inventionare not harmful to plants or seeds and, mercaptan of Example 1 and anequivalent weight of the therefore, plants or seeds can be present inthe soil at indicated isocyanatefor the methyl isocyanate of Exthe timeof treatment or put into treated soil after treatample 1.

Ex. Mereaptan Isoeyanate Product 2 Allyl mercaptan Methyl isoeyanateDiallyl N,N-bis(methylearbamoyloxy) dithioloxalimidate 3 Ethylmercaptan.-. Ethyl 1socyanate Diethyl N,N-bis(ethylcarbamoyloxy)dithioloxalimidate. 4-- Sec-butyl mercapta Methyl 1socyanateDgsigcliltalglN,N-b1s(methylcarbamoyloxy) dithiolox- 5 Methyl mercaptanTert-butyl isocyanate DimetliiyltbhN bis(tert-butylcarbamoyloxy)dithioloxlml a e. 6 do Crotyl isocyanate Dir neth yl N,N-bis(crotylcarbomoyloxy) dithioloxlIIll a e. 7 do PropargylisocyanateDismgtilggltq,N-bis(propargylcarbamoyloxy) dithiolox- 8 But-Z-enylmercaptan Methyl isocyanate Digbutg-enkrl) N,N-bis(methylcarbamoyloxy)dithiolox- 11111 a 6. 9 Methyl mercaptan But-2-enyl isocyanate DirlnethiyltN,N-bis(but-Z-enycarbamoyloxy) dithioloxment. The use ratesfor this type application are the same EXAMPLE 10 as for the soilincorporation procedure outlined above.

methods of of .05; it: etzist tzzsi t asertia zisztthziivention toprevent the destructive effects of plant-parasitic captan at C Then 32parts 50% Sodium hydroxide is nematodfis Include: (a) Sprayingaljove'ground parts added at 010 C. to give 32 parts diethylmercaptosuchas stems, leaves or buds in which nematodes are glyoxime which has 2 MPof 80 95c C after recrystab already present or where later attack ispossible; (b) Elation from benzene p addition to transplant water; (c)dipping or soaking re- T h h dd d 15 6 productive parts, such as seeds,cane pieces or bulbs met p g g en a g f g which are already infested orare to be planted in inyrlnercaPtog g g met fested soil, in a watersuspension, solvent solution or .i g gi h 5 b to yi. l i emulsion of theactive ingredient; (d) immersing the root y i lsunet ia OX3 umsystem orentire plant of nursery stock or transplants 3 er recryst 123mm mm touene'aceto' in an aqueous, solvent or emulsion system of the active mmlehas a of 164-166 ingredient of this invention to disinfest the plant andpro- EXAMPLE 11 vide residual protection against subsequent nematodeinvasion. The concentration of active ingredient in such To 31.4 partsdichloroglyoxlme in 125 parts ethyl alsprays, transplant water or dipsis between 5 to 5,000 601101 and 125 Parts WatQr addefi Parts P P'Ygrams per 100 liters of water or other liquid carrier, and mefflaptallat C. To thls System addqd 32 Parts preferably between 10 and 2,500grams per 100 liters. The 0d111m hydwxlde at W P glVeS 15 Parts mostpreferred concentrations are between 25 and 1,500lsopropylmefcflptoglyoiilmee which after 1W0 l'ecfystallilagrams er1001it of r i tions from benzene has a M.P. of 132-135 C.

A dry dust formulation of the compounds of this in- Sevel} parts methyllsocyanate then added t 11.8 vention can be used in place of the liquidsystem in all Parts dllsopfopylmefcaptoglwxlme 111 150 Parts of methofthe applications listed above. These dust formulations ylelle'chlorldesolvent 15 fefnoved after 4 hours to will contain from 1 to 60weight percent of active ine 12 n r s p py y y qw) gradient, and ll f o2 to 30 weight Percent f dithioloxalrmldate, M.P. 16 0- 162 C. afterrecrystalhzaactive ingredient. The most preferred rates are in the fromtolueneacetommla range of from 3 to 15 weight percent of activeingredient.

An important attribute of the compounds of this in- EXAMPLE 12 ventionis that, under some circumstances, they enter the To 18 partsdimethylmercaptoglyoxime in 250 parts plant roots from the soil and movethroughout the root methylene chloride is added 22 parts allylisocyanate. system. This means that even those portions of the rootWorkup after two days gives 25 parts dimethyl N,N'-bissystem outside ofthe treated soil can, in some cases, be(allylcarbamoyloxy)dithioloxalimidate, M.P. 144148 C. protected fromnematode damage. after recrystallization from benzene.

1 1 EXAMPLE 13 To 18 parts dimethymercaptoglyoxime in 250 partsmethylene chloride is added 20 parts ethyl isocyanate. Workup after twodays gives 23.3 parts dimethyl N,N'-bis(ethylcarbarnoyloxy)dithioloxalimidate, M.P. 182- 184 C. afterrecrystallization from benzene-acetonitrile.

EXAMPLE 14 To 60 parts glyoxime in 800 parts ethyl alcohol and 800 partswater is added 100 parts chlorine at a temperature of from -10 C. Thereaction mixture is allowed to stand overnight. Then 33.5 parts methylmercaptan, at a temperature of from 0-10 C., is slowly added to thisreaction mixture followed by the addition of sufficient 50% aqueoussodium hydroxide to raise the pH to 7. Then 50.5 parts of allylmercaptan is added to the reaction mixture followed by sufficient 50%aqueous sodium hydroxide to neutralize the reaction mixture. The resulting l-allylrnercapto 2 methylmercaptoglyoxime is filtered from thereaction mixture, and can be further purified by recrystallization frombenzene.

To 20.6 parts 1-a1lylmercapto-2methylmercaptoglyoxirne suspended in 200parts methylene chloride is slowly added 2.9 parts methyl isocyanate.This reaction mixture is allowed to stand for 3-5 hours after which 4.3parts n-propyl isocyanate is added. The reaction mixture is againallowed to stand for another 3-5 hours after which allyl methylN-methylcarbamoyloxy)-N'-(n-propylcarbamoyloxy)dithioloxalimidate isrecovered by filtration.

EXAMPLES 15-18 The indicated products can be prepared by the procedureof Example 14 by substituting in the order listed an equivalent weightof each indicated mercaptan for methyl mercaptan and allyl mercaptanrespectively of Example 14 and an equivalent weight of each indicatedisocyanate for methyl isocyanate and n-propyl isocyanate respectively ofExample 14.

Wettable powders with equally satisfactory control of nematodes can beprepared \by replacing the diethyl N,N'-bis(rnethylcarbamoyloxy)dithioloxalimidate of the formulation of Example19 with any of the following compounds of this invention:

dimethyl N,N'- bis(methylcarbamoyloxy)dithioloxalimidate diisopropylN,N'-bis (methylcarbamoyloxy dithioloxalimidate dimethyl N,N-bis(ethylcarbamoyloxy) dithioloxalirnidate EXAMPLE 20 The followingingredients are formulated as a wettable powder according to the methodof Example 19:

The resulting formulation is suitable for dispersion in either oil orwater for application to soil.

This wettable powder is dispersed in water at the rate of 7 kilograms ofwettable powder per 100 liters of Watter. The resulting suspension issprayed at the rate of 400 liters per hectare on test plots within afield in New York known to contain high populations of northern rootknotnematode (Meloidogyne hapla). Promptly following this application, thechemical is thoroughly mixed into the soil to a depth of 10 to 15centimeters with a rotovator. Head lettuce plants set into the treatedsoil are protected from attack by the nematodes and grow well to producea good yield of high-quality heads. Head lettuce planted in similar butuntreated soil grows poorly and yields few marketable heads due todamage to the root systems by the northern root-knot nematode.

The active component in Example 20 can be replaced Ex. MercaptanMercaptan Isocyanate Isoeyanate Product 15 n-Butyl mercaptan- Methylmercaptan. Ethyl isocyanate... Methyl isocyanate Butyl methylN-(ethylcarbamoyloxy)-N-(methylcarbamoyloxy) dithioloxalimidate.

16 Methyl mercaptan .do Allylisocyanate do DimethylN-(allylcarbamoyloxy) N-(methylcarbamoyloxy) dithioloxalimidate.

17 But-2-enyl-mercaptan do Methyl isocyanate do But-Q-enyl methylN,N-bis- (methylearbamoyloxy) dithioloxalimidate 18 Methyl morcaptanIsopropyl mercaptam Allyl isocyanate Isopropyl isocyanate. Methylisopropyl N-(allyl- EXAMPLE 19 A wettable powder is prepared by blending80 parts diethyl N,N'-bis (methylcarbamoyloxy) dithioloxalimidate With 2parts alkyl naphthalene sulfonic acid, sodium salt, one part partiallydisulfonated sodium lignin sulfonate and 17 parts synthetic silica. Thismixture is then micropulverized until substantially all particles arebelow microns and then reblended. The resulting powder wets anddisperses readily in water.

The wettable powder of Example 19 is dispersed in water in aconcentration of 5 kilograms of powder per 100 liters of water. Thisdispersion is applied to the surface of the soil, broadcast, at a ratesufficient to provide from 2 to 25 kilograms of active ingredient perhectare of land treated. After the dispersion is sprayed onto thesurface of the soil, it is mixed in the soil to a depth of 10 to 15centimeters with a rotovator or other tillage equipment.

Cotton plants grown in soil infested with southern root-knot nematode(Meloidogyne incognita) show normal development, free from nematodeinfection, when the soil is treated as described above. Cotton plantsgrown in similar but untreated soil show stunting, and reduced yieldsdue to nematode infection.

carbamoyloxy)-N-(isopropylearbamoyloxy) dithioloxalimidate.

by any of the following compounds to give an equally satisfactoryformulation:

dimethyl N,N' bis (methylcarb amoyloxy) dithioloxalimidiri fdlliylN,N'-bis (allylcarbamoyloxy) dithioloxalimidi lzliyl N,N'-bis(methylacarbamoyloxy) dithioloxalimidlf i liliyl N,N'-bis(ethylcarbamoyloxy) dithioloxalimidate EXAMPLE 21 13 develop anextensive root system essentially free of rootknot, make rapid growthand produce a good yield. The untreated tobacco plants grow slowly andproduce little marketable leaf.

EXAMPLE 22 For the simultaneous control of the root-knot nematode(Meloidogyne incognito) and soil fungi as represented by Pythium spp.and Rhizoctonia spp., the wettable powder formulation of Example 21 isapplied in a spray which also contained1,4-dichloro-2,S-dimethoxybenzene. For this type of application, 2.4kilograms active of the composition of this invention and 4.8 kilogramsactive of 1,4-dichloro-2,S-dimethoxybenzene is added to 100 liters ofwater. This mixture is applied as a soil spray by application to a 25centimeter band over the row in which cotton is to be planted. Theapplication rate on the row is 67.5 kilograms of total active (22.5kilograms of the compound of this invention and 45 kilograms of1,4-dichloro-2,S-dimethoxybenzene) per hectare of area actually treated.The soil is rotovated immediately thereafter to mix the chemicalsthoroughly with the soil in the treated band. Following this, cottonseed is planted in the treated band. The cotton seedlings which developare protected against root-knot nematode (Meloiodogyne incognita) andthe fungi Pythium spp. and Rhizoctonia spp. A healthy stand of cottonplants is obtained and at harvest time with a high yield of lint. Whereno treatment is applied, the stand is poor, growth is 510W and lintyield is reduced.

Even much higher use rates than those given above are employed withcomplete safety to the cotton plants.

EXAMPLE 23 A formulation is prepared according to the method of Example20 but substituting N,N'-bis(allylcarbamoyloxy)- dithioloxalimidate asthe active ingredient.

The formulation is dispersed in water and sprayed at the rate of 40kilograms of active ingredient in 100 decaliters of water per hectare ofa Zoysia lawn in Florida where the soil is heavily infested with stingnematode (Belonolaimus longicaudatus). After spraying, the material iswashed into the ground with an irrigation equivalent to about 20,000'decaliters of water per hectare. The grass in the treated area developsa deep root system and makes rapid growth, whereas grass in a similarbut untreated area grows slowly and develops only a shallow root systemdue to attack by the sting nematode.

EXAMPLE 24 A formualtion is prepared according to the method of Example20 but substituting diethyl N,N'-bis(methylcarbamoyloxy)dithioloxalimidate as the active ingredient.

This formulation is added to Water at the rate of 2 grams per liter.Narcissus bulbs infested with the bulb and stem nematode (Ditylenchusdipsaci) are dipped in this diluted preparation for a period of 30minutes. The suspension is agitated frequently during the period. Thetreated bulbs planted in field soil grow to produce good yields of bothcut flowers and new bulbs. Similarly infected bulbs that are not treatedgrow poorly giving only small yields of both flowers and bulbs.

EXAMPLE 25 A formulation is prepared according to the method of Example20 but substituting dimethylN,N'-bis(ethylcarbamoyloxy)dithioloxalimidate as the active ingredient.

This formulation is added to water at the rate of grams per liter. Theroots and lower stem of woody nursery stock known to be infested withthe lance nematode (Hoplolaimus coronatus) are dipped in this suspensionfor three minutes in such a way as to keep the suspension agitated. Whenstock so treated is planted it grows well and is of good appearance.Similar stock which is not treated grows poorly, is of poor appearanceand, in many cases, does not survive.

14 EXAMPLE 26 A wettable powder is prepared by blending 25 partsdimethyl N ,N' bis(methylcarbamoyloxy)dithioloxalimidate, 1 part dioctylsodium sulfosuccinate, 2 parts partially disulfonated sodium ligninsulfonate and 72 parts attapulgite clay. This mixture is thenmicropulverized until substantially all particles are below 50 microns.

This wettable powder is added to water and sprayed on selected plots ina strawberry field known to be heavily infested with the bud and leafnematode, A phelenchoz'des besseyi. The spray solution contains 300grams active of the composition of this invention per 100 liters ofwater. The rate of application is such as to provide 3 kilograms of theactive ingredient per hectare of plot area. All aboveground parts arethoroughly wetted. The strawberry plants in the sprayed plots grow welland give a good yield. In the unsprayed portions of the field, on theother hand, the plants are yellow, grow slowly and produce a poor yield.

EXAMPLE 27 A suitable dust concentrate is prepared by blending partsdimethyl N,N'-bis(allylcarbamoyloxy)dithioloxalimidate with 20 partsmicaceous talc. This mixture is then micropulverized until substantlallyall particles are less than 100 mesh. This dust concentrate can bediluted to desired strength by a custom formulator using micaceous talcor other diluents for field application as a dust.

This dust concentrate is prepared for field application by the additionof sufiicient micaceous tale to provide a final dust containing 5% ofthe active ingredient. The resulting 5% dust is dusted into alternateopen furrows, with seed pieces in place, in a sugarcane fie d inFlorida. The dust is applied at a rate to provide 0.5 kilogram of theactive ingredient per 1,000 linear meters of furrow. The dust stream isdirected to cover the sides of the furrow as well as the bottom. Thefurrows are then closed. Ten weeks after planting the treated rowscontain full stands of thrifty and welldeveloped cane. The cane in theuntreated rows, on the other hand, is stunted with an unthrifty yellowappearance due to root damage caused by nematodes such as the lancenematodes, Hoplolaimus spp., spiral nematodes, Helicotylenchus spp., andstunt nematodes, tylenchorhynchus spp.

EXAMPLE 28 A dry mix is prepared comprising 5% dimethyl N,N'-bis(methylcarbamoyloxy)dithioloxalimidate and the remainder gypsum andammonium sulfate. These ingredi ents are mixed in a cement mixer andwhile mixing continues water is sprayed on until balling of the mixtureoccurs. The balled mix is dried, crushed and screened to separategranules having a particle size of from- 20 to 60 mesh. These granulesare readily disintegrated in water and provide rapid release of theactive ingredient.

These rapid release granules are applied at the rate of 40 kilograms ofactive ingredient per hectare to plots in a field using a conventionalfertilizer spreader. The material is then worked into the soil bydiscing. Tobacco plants grown in soil infested with the lesion nematode,pratylenchus brachyurus and the southern rootknot Meloidogyne incognitogrow and yield well substantially free from nematode infection, when thesoil is treated as described above. Tobacco plants grown on untreatedplots in the same field grow slowly and produce little marketable leaf.

EXAMPLE 29 Five parts dimethyl N,N'-bis(allylcarbomoyloxy)-dithioloxalimidate is dissolved in boiling alcohol. This solution issprayed on parts corncob granules, 30 to 60 mesh, in a rotating drumafter which the alcohol is evaporated.

This granular formulation is applied evenly at a rate of 20 kilograms ofactive ingredient per hectare to plots within a field known to beinfested with the sugar beet 15 nematode, Heterodera schachtii. Thisapplication is worked into the soil to a depth of to centimeters. Sugarbeets subsequently grown in the treated plots delevop normally and aresubstantially free from infestation 'by nematodes. Beets grown inuntreated plots in the same field are distorted and produce reducedyields.

EXAMPLE 30 A mixture of 5 parts dimethyl N,N'-bis(ethylcarbamyloxy)dithioloxalimidate and 1.25 parts synthetic finesilica is micropulverized and then micronized. This powder is blendedbriefly with 83.75 parts to 40 mesh vermiculite in a rotating drum. Then10 parts ethylene glycol is sprayed upon the vermicculite active mitxureto prevent separation of powder from verimculite. Mineral oil,nonylphenoxy polyethylene oxide or other fiowable liquid with very lowvolatility can be used as the sticking agent.

The granular formulation prepared above is applied at the rate of 0.25kilograms of active ingredient per 1,000 linear meters of row in theopen furrow at the same time that celery plants are set in a field knownto be infested with the awl nematode, Dolichodo'rus heterocephalus. Onlyalternate rows are treated with the above prepared formulation: Thecelery plants in the treated rows grow rapidly and yield well. Theentire root systems of the plants in the treated rows are free fromnematode injury even through treatment was limited to the furrow area.The protection of those roots growing outside the soil actually treatedis ascribed to the systemic movement of the active ingredient of thisinvention within the celery roots. The celery plants in the untreatedalternate rows are severely stunted due to attack by the awl nematode.

It is to be understood that the foregoing examples are given forpurposes of illustration only and other compounds of this invention canbe substituted for the active materials used above.

I claim:

1. A nematocidal composition consisting essentially of an inert diluentand a nematocidally effective amount of a compound of the formulawherein:

R and R can be the same and different, and are selected from the groupconsisting of alkyl of one through four carbons and alkenyl of threethrough four carbons; and

R and R can be the same and different and are selected from the groupconsisting of hydrogen, alkyl of one through four carbons, alkenyl ofthree through four carbons and propargyl.

2. A nematocidal composition consisting essentially of an inert diluentand a nematocicdally effective amount of a compound of claim 5 wherein Rand R are the same and are selected from the group consisting of alkylof one through four carbons and alkenyl of three through fur carbons;and

R and R are the same and are selected from the groups consisting ofhydrogen, alkyl of one through four carbons, alkenyl of three throughfour carbons and propargyl.

3. A nematocidal composition consisting essentially of an inert diluentand a nematocidally effective amount of dimethylN,N-bis(methylcarbamoyloxy)dithioloxyalimidate.

4. A nematocidal composition consisting essentially of an inert diluentand a nematocidally effective amount of dimethyl N,N'bis(ethylcarbamyloxy) dithioloxalimidate.

5. A method of controlling nematodes comprising applying to the area ofnematodal infestation a nematocidally effective amount of a compound ofthe formula:

R and R can be the same and different, and are selected from the groupconsisting of alkyl of one through four carbons and alkenyl of threethrough four carbons; and

R and R can be the same and different, and are selected from the groupconsisting of hydrogen, alkyl of one through four carbons, alkenyl ofthree through four carbons and propargyl.

6. The method of claim 5 wherein the nematocidally effective compound isa compound of the formula R1S S-Rz wherein:

R and R are the same and are selected from the group consisting of alkylof one through four carbons and alkenyl of three through four carbons;and

R and R are the same and are selected from the group consisting ofhydrogen, alkyl of one through four carbons, alkenyl of three throughfour carbons and propargyl.

7. The method of claim 5 wherein the compound being applied is dimethylN,N'-bis(methylcarbamoyloxy)- dithioloxalimidate.

8. A method for protecting reproductive plant parts from nematodalinfestation comprising coating said part with a nematocidally effectiveamount of dimethyl N,N- bis(methylcarbamoyloxy) dithioloxalimidate priorto the planting of said seeds.

9. The method of claim 8 wherein the nematocidally effective compound isdimethyl N,N-bis (ethylcarbamoyloxy) dithioloxalimidate.

References Cited UNITED STATES PATENTS 3,337,396 8/1967 Spurr 4243273,385,691 5/1968 Strycker 7177 XR ALBERT T. MEYERS, Primary Examiner D.R. ORE, Assistant Examiner US. Cl. X.R.

